Jim if you go to the home page and scroll to the bottom you will see a link that reads "advertise with us". We have companies paying for advertising and if we let you post with a link to the product for purchase they will rightly ask why they are paying to advertise.

I should also say that I agree that diffraction control is important and that is why I use it with my own speakers. I use a home made method of felt with adhesive backing designed to protect furniture. I became aware of the need years ago when reading about a speaker designer and he used self-adhesive foam used to insulate doors and windows to surround the tweeters.